"For Arena matches lasting longer than 15 minutes, one of the teams will receive a buff called "The Crowd Chose You" that increases damage, critical strike chance, stealth detection, and reduces damage taken. The buff is awarded based on the following criteria.

Team with the largest number of players alive. Team that brought an enemy player closest to death (lowest health)."

Why in the world do you think LFR style will work for the best in arenas?

So If our 3rd fails to join in, and we are widdle down a 2v3 in arenas you give the other team a buff just to end it?

I would Rather lose by Draw or Lose Fairly then have the other team 'Take less damage and deal more damage' to win not by skill not by gear no by PVE gear but because they got a free buff?!

Really super long arena matches are so rare in my experiences. Only ever happened to me in Wrath a few times when I tried out Blood DK spec for jollies with my Shaman buddy in 2's and as Hunter/Holy Pally when I died and they couldn't kill my holy pally. That's about it.

This is the important thing to remember here, I think. The number of matches that actually go past 15 minutes is incredibly small -- less than half a percent. Realistically, very few players will probably ever see "The Crowd Chose You" come into play at all.

However, the games that do last that long typically fall into the category that Ugluc mentioned: one team clearly has no chance of winning, but the other team is having trouble closing the deal. The current system (ending in a draw) essentially means that everyone loses. In those extremely rare cases, we'd rather award the win to the team that got closest to victory.

That said, we're also trying to avoid doing anything that would change how you play a normal match. This is actually why we don't like the idea of a debuff with a ramp-up time: it becomes something that certain teams will want to strategize around. We recognize that there are concerns with abilities such as Ice Block, Guardian Spirit, and so on. We share those concerns and want to avoid changing how you use those abilities as much as possible.

Remember, this is the PTR. "Test" is quite literally its middle name. Things can easily change before the patch goes live. However, we do feel that this system, whatever final form it takes, will be a large improvement over the current "everyone loses" scenario.